package jiexi;
import java.util.Arrays;
public class Dell55AA01Parser {
	// 常量定义
	private static final String EXPECTED_HEADER = "55AA01"; // 协议头
	private static final int MIN_LENGTH = 42; // 最小长度(21字节*2字符)
	private static final ThreadLocal<ParseResult> RESULT_CACHE = 
			ThreadLocal.withInitial(ParseResult::new);

	// 解析结果类
	public static class ParseResult {
		public int sequenceNum;   // 序列号
		public String tagId;      // 标签ID(4字节小端序)
		public String anchorId;   // 锚点ID(4字节小端序)
		public int distance;      // 距离(毫米)
		public int power;         // 电量(0-100)
		public int buttonPressed; // 按钮状态
		public boolean buttonPressed2;
		public void reset() {
			sequenceNum = 0;
			tagId = "";
			anchorId = "";
			distance = 0;
			power = 0;
			buttonPressed = 0;
			buttonPressed2=false;
		}
	}

	/**
	 * 解析55AA01协议数据
	 * @param message 十六进制字符串
	 * @return 解析结果(错误时返回null)
	 */
	public static ParseResult parse(String message, String ip, int port) {
		if (message == null || message.isEmpty()) {
			return null;
		}

		// 清洗数据：移除所有非十六进制字符
		char[] cleanedMessage = cleanMessage(message);

		// 数据校验
		if (cleanedMessage == null || cleanedMessage.length < MIN_LENGTH) {
			return null;
		}

		// 协议头校验 (55AA01)
		if (!new String(cleanedMessage, 0, 6).equals(EXPECTED_HEADER)) {
			return null;
		}

		ParseResult result = RESULT_CACHE.get();
		result.reset();

		try {
			if (cleanedMessage.length < 30) { // 确保有足够长度访问charAt(28)
				return null;
			}

			// 解析序列号 (位置8-9)
			result.sequenceNum = HexUtils.fastHexToByte(cleanedMessage[8], cleanedMessage[9]);

			// 解析标签ID (位置10-13, 小端序)
			result.tagId = new String(new char[]{
					cleanedMessage[12], cleanedMessage[13], // 高位
					cleanedMessage[10], cleanedMessage[11]  // 低位
			});

			// 解析锚点ID (位置14-17, 小端序)
			result.anchorId = new String(new char[]{
					cleanedMessage[16], cleanedMessage[17], // 高位
					cleanedMessage[14], cleanedMessage[15]  // 低位
			});

			// 解析距离 (位置18-25, 4字节小端整数)
			int b0 = HexUtils.fastHexToByte(cleanedMessage[18], cleanedMessage[19]); // 最低位
			int b1 = HexUtils.fastHexToByte(cleanedMessage[20], cleanedMessage[21]);
			int b2 = HexUtils.fastHexToByte(cleanedMessage[22], cleanedMessage[23]);
			int b3 = HexUtils.fastHexToByte(cleanedMessage[24], cleanedMessage[25]); // 最高位
			int raw = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
			result.distance = raw; // 保持原始整数值

			// 解析电量 (位置26-27)
			result.power = HexUtils.fastHexToByte(cleanedMessage[26], cleanedMessage[27]);

			// 解析按钮状态 (位置28-29)
			result.buttonPressed = HexUtils.fastHexToByte(cleanedMessage[28], cleanedMessage[29]);
			result.buttonPressed2 =result.buttonPressed==1;			

		} catch (IndexOutOfBoundsException | NumberFormatException e) {
			System.err.println("Parsing error in packet from " + ip + ":" + port);
			return null;
		}

		return result;
	}

	private static char[] cleanMessage(String message) {
		char[] cleaned = new char[message.length()];
		int j = 0;
		for (char c : message.toCharArray()) {
			if (Character.isDigit(c) || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f')) {
				cleaned[j++] = Character.toUpperCase(c);
			}
		}
		if (j == 0) return null;
		return Arrays.copyOf(cleaned, j);
	}
	
}